(a) Field of the Invention
The present invention relates to a method and apparatus for controlling inter-beam interference, and more particularly, to a method and apparatus for controlling inter-beam interference to mitigate interference between adjacent beams in a stationary multi-beam-based mobile communication system.
(b) Description of the Related Art
Driven by the growth of the IoT (Internet of Things), the rapid spread of smart devices, and the advent of immersive UHD (Ultra High Definition) service, mobile traffic is increasing at a rapid pace and is expected to be more than 1000 times the current rate by 2020. In order to transfer and process this increasing mobile communication traffic, there is a need for 5G mobile communication systems to use new frequency bands that provide wider bandwidth. In the light of this, the industry is looking at the use of 30 to 300 GHz millimeter wave bands.
The millimeter wave bands have a wider range of coverage and make continuous allocation of radio resources easier, compared to bands below 3 GHz used in traditional mobile communication networks, which can lead to an increase in the capacity of communication systems. However, millimeter waves propagate in straight lines and cause high propagation loss. To overcome these problems, beamforming techniques on massive antenna arrays are used in millimeter wave-based mobile communication systems.
Beamforming techniques can be divided into fixed beamforming and adaptive beamforming. Fixed beamforming is preferred because of its comparatively low hardware complexity and low operating overhead. Each beam generated by fixed beamforming constitutes a small beam region in which frequency resources are re-used, thus greatly enhancing transmission efficiency of terminals through space-division multiple access.
With space-division multiple access techniques based on conventional fixed beamforming, however, beams overlap to prevent coverage holes, and all beams are constantly emitted. Due to this, terminals in beam overlapping areas are highly affected by inter-beam interference, and have poor signal-to-interference-plus-noise ratio (SINR) performance. Thus, it is difficult to expect an increase in service capacity.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.